US president Donald Trump is expected to pull the United States from a landmark global climate agreement, a White House official said - though there could be "caveats in the language" announcing a withdrawal, leaving open the possibility that his decision is not final.
xiting the deal would fulfil a central campaign pledge from the president, but would be certain to anger allies that spent years negotiating the accord to reduce carbon emissions.
The official insisted on anonymity in order to discuss the decision before the official announcement.
Mr Trump tweeted yesterday morning: "I will be announcing my decision on the Paris Accord over the next few days. MAKE AMERICA GREAT AGAIN!"
While Mr Trump currently favours an exit, he has been known to change his thinking on major decisions and tends to seek counsel from a range of inside and outside advisers, many with differing agendas, until the last minute.
The president's top aides have been divided on the accord. Yesterday afternoon, Mr Trump was meeting Secretary of State Rex Tillerson, who has favoured remaining in the deal.
Chief strategist Steve Bannon supports an exit, while senior adviser Jared Kushner thinks the deal is bad, but would like to find a way to see if the US emissions targets can be changed.
Nearly 200 nations, including the US under former president Barack Obama's administration, agreed in 2015 to voluntarily reduce their greenhouse gas emissions in an effort to combat climate change. Withdrawing would leave the US aligned only with Russia among the world's industrialised economies in rejecting action to combat climate change.
Mr Trump pledged during his presidential campaign to withdraw the US from the pact immediately after taking office, but had wavered on the issue since winning the election.
During Mr Trump's overseas trip last week, European leaders pressed him to keep the US in the pact. French President Emmanuel Macron spoke with Mr Trump at length about the issue during a meeting in Brussels, and even at the Vatican, Cardinal Secretary of State Pietro Parolin made his own pro-Paris pitch to the US president and his advisers.
News of Mr Trump's expected decision drew swift reaction.
The United Nations' main Twitter page quoted Secretary-General António Guterres as saying: "Climate change is undeniable. Climate change is unstoppable. Climate solutions provide opportunities that are unmatchable."
US environmental group The Sierra Club's executive director Michael Brune called the expected move a "historic mistake which our grandchildren will look back on with stunned dismay at how a world leader could be so divorced from reality and morality".
Mr Trump claimed before taking office that climate change was a "hoax" created by the Chinese to hurt the US economy. Such an assertion stands in defiance of broad scientific consensus.
But chief White House economic adviser Gary Cohn told reporters during the trip abroad that Mr Trump's views on climate change were "evolving" following the president's discussions with European leaders.
Word of Mr Trump's expected decision comes a day after the president met Scott Pruitt, the administrator of the US's Environmental Protection Agency.
Mr Trump and Mr Pruitt have moved to delay or roll back federal regulations limiting greenhouse gas emissions while pledging to revive the long-struggling US coal mines.
What is not yet clear is whether Mr Trump plans to initiate a formal withdrawal from the Paris accord, which under the terms of the agreement could take three years, or exit the underlying UN climate change treaty on which the accord was based.